Logic Map for Proving P → Q

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Logic Map for Proving P → Q P Q ¬Q ¬P Contradiction (⊥) Direct proof (P → Q) Contrapositive (¬Q → ¬P) Contradiction (P ∧ ¬Q → ⊥)
Direct assume P ⇒ … ⇒ Q
Contrapositive assume ¬Q ⇒ … ⇒ ¬P
Contradiction P ∧ ¬Q ⇒ ⊥